Theory: Wii U is part of the fusion concept and will be around longer than we think.

[Platina]

Interesting theory... but I highly doubt that they will hold off until the PS5/XTwo is released....

Though continuing to support the Wii U would be great, I don't really see them having the need to hold back the next console. The Wii U already had many major hitters released and sales didn't improve to the extent that Nintendo wants. In fact, I'd think that they would push for the next console as quickly as possible so though it would be 'underpowered' it could rival against the PS4/XOne. A somewhat fresh start with a new console is better than holding off.